The present invention relates to an actuator for an inhaler for administering medicament by inhalation and to an inhaler including the same.
For some time, actuators have been known for delivering metered doses of medicament from aerosol canisters. These actuators comprise a single integral moulding and are usually coloured to identify the medicament being delivered. After use with only one canister the actuator is discarded. This is desirable, since some medicaments which are delivered, will, over time, become deposited in the nozzle block and the mouthpiece of the actuator.
It is an aim of the present invention to provide an actuator of two-part construction, with an outlet assembly thereof, which comprises those components which normally come into contact with medicament, being securely held in position in relation to the main body thereof even in the absence of an aerosol canister, but being capable of being detached as required.
The provision of a detachable outlet assembly is especially applicable where the actuator is sophisticated and hence relatively expensive, such as an actuator which includes a breath actuation mechanism or a compliance monitor, since it is not necessary to dispose of the entire actuator after exhaustion of the canister. Rather, a new outlet assembly may be fitted together with a new canister.
The two-part construction of an actuator further allows for the manufacture of a range of actuators by providing the outlet assembly as a first part common to the range and forming the main body as a second part from any material and optionally in any shape. Typically, the main body can be coloured or have a particular surface finish or decoration according to the medicament to be delivered. In addition, the main body can be formed to have a particular shape, such as that of an animal which may appeal to young children.
It will further be appreciated that this two-part construction is also advantageous for preparing regulatory documentation which will include common data relating to the outlet assembly.
WO-A-95/07723 discloses an actuator for an inhaler which includes a replaceable mouthpiece, but in the absence of an aerosol canister the mouthpiece can be slid out of the main body, thereby requiring no release component to effect release of the mouthpiece from the main body.
Accordingly, the present invention provides an actuator for an inhaler for administering medicament by inhalation, comprising: a main body comprising an elongate tubular member for receiving a canister containing medicament and having a valve stem extending therefrom, the tubular member including a lateral opening at one end thereof; and an outlet assembly comprising a mouthpiece for guiding medicament to the mouth of a user and a nozzle block for receiving the valve stem of the canister and delivering medicament from the canister into the mouthpiece, the outlet assembly being detachably mounted, through the lateral opening, to the main body at an angle transverse to the length of the tubular member; characterized in that one of the main body and the outlet assembly further comprises at least one resiliently biased member, which is configured to engage with at least one part of the other of the main body and the outlet assembly and thereby hold the outlet assembly to the main body, and at least one release component which in use is acted upon to enable release of the outlet assembly from the main body.
Preferably, the tubular member includes a further opening at the other end thereof through which a canister is in use fitted.
Preferably, the main body further comprises a foot at the one end of the tubular member which is configured such that, with a canister fitted therein, the actuator will stand unsupported with the tubular member extending generally vertically.
In one embodiment the bottom surface of the foot includes a recess for receiving a thumb or a finger of a user. Preferably, the recess is concave.
In another embodiment the bottom surface of the foot is flat.
Preferably, the actuator further comprises a breath actuation mechanism.
Preferably, the actuator further comprises a compliance monitor, in particular a dose counter.
In a preferred embodiment the main body comprises one or both of the breath actuation mechanism and the compliance monitor.
In a particularly preferred embodiment the foot comprises one or both of the breath actuation mechanism and the compliance monitor.
Preferably, the main body and the outlet assembly are composed of materials having different constitution.
In one embodiment the main body and the outlet assembly are composed of entirely different materials.
In another embodiment the main body and the outlet assembly are composed of the same basic material but include different additives such as colour pigment.
In a preferred embodiment the main body and the outlet assembly are of different colour.
Preferably, the outlet assembly is formed as a single integral moulding.
Preferably, the nozzle block includes a bore having an opening for receiving the valve stem of a canister and a spray orifice configured to direct a spray into the mouthpiece.
Preferably, the outlet assembly comprises first and second resiliently-biased arms which each support a catch member and the main body comprises first and second projections which extend inwardly from an inner surface thereof, the catch members on the first and second arms and the projections on the main body being arranged to engage one another when the outlet assembly is inserted fully into the main body.
Preferably, the first and second arms are radially opposed.
Preferably, the first and second arms extend rearwardly.
Preferably, the main body includes at least one opening for accessing the at least one release component.
More preferably, the at least one opening is provided in the foot of the main body.
Preferably, the at least one release component comprises a part which extends into or through the at least one opening.
More preferably, the at least one release component comprises first and second projections disposed on an interconnecting element which interconnects the catch members on the first and second arms such that when the projections on the interconnecting element are acted upon the catch members on the first and second arms are disengaged from the respective projections on the main body so as to allow withdrawal of the outlet assembly from the main body.
Preferably, the outlet assembly further comprises a further resiliently-biased arm which extends at an angle downwardly from the nozzle block, the distal end of the further arm including a catch member which, when the outlet assembly is inserted fully into the main body, engages behind a part of the tubular member defining the lateral opening.
More preferably, the further arm extends forwardly.
Preferably, the at least one release component further comprises a projection which extends downwardly from the further arm.
Preferably, the outlet assembly further comprises a second further resiliently-biased arm which supports a catch member, which, when the outlet assembly is inserted fully into the main body, engages behind a part of the tubular member defining the lateral opening.
More preferably, the second further arm extends rearwardly.
The present invention also extends to an inhaler comprising the above-described actuator and a canister containing medicament.
Preferably, the inhaler is a pressurised metered dose inhaler.